1. Field of the Invention
The present invention relates to a foamed plastic molding suitable for molding foamed plastic articles such as to be used for car seat cushions and seat backs in conjunction with skin covers.
2. Description of the Background Art
Car seat cushions and seat backs have been made of a pad member covered by a skin cover. The pad member and the skin cover used to be manufactured separately and combined together later, but it has become fashionable to manufacture a skin covered pad member altogether by forming foamed plastic in a skin cover laid over a mold, so that the process of combining at later time may be omitted.
However, the contemporary car seats tend to have large side support portions with large curving so that it becomes difficult to place the skin cover neatly over the mold. As a consequence, in order to obtain a skin covered pad member of desired shape it is necessary for a skin cover to be pinned down or taped to the mold, which is an additional complication in the manufacturing process.
One manner to cope with this situation has been disclosed by the present inventor in Japanese Patent Application (Laid Open) No. S61-280908.
Here, as shown in FIG. 1, there is provided a mold 11 comprising an upper mold 12 and a lower mold 13. The lower mold 13 further comprises a fixed part 13a with receiving edges 15a and 15b, and a movable part 13b movably supported by a supporting rod 16. Outer where outer edges 14a and 14b of the movable part 13b are caught by the receiving edges 15a and 15b at a lowered position.
In manufacturing a skin covered foamed plastic article, a skin member 21 is attached to the movable part 13b at a raised position with a middle portion 21a along an inner surface of the movable part 13b, and side portions 21b and 21c corresponding to the fixed part 13a rolled behind and fastened underneath the movable part 13b by means of pin members 18a and 18b, respectively, before lowering into a position in which the outer edges 14a and 14b of the movable part 13b are engaged with the receiving edges 15a and 15b of the fixed part 13a, as shown in FIG. 2. Then, liquid foamed plastic 26 is poured over the lower mold 13 from a nozzle 30 as in FIG. 2, and the upper mold 12 is placed over the lower mold 13 so as to form a foamed plastic pad member 25 of desired shape, automatically combined with the skin member 21, as in FIG. 3. This partially skin covered foamed plastic pad member 25 is then taken out from the mold 11, and the side portions 21b and 21c of the skin member 21 are rolled around the foamed plastic pad member 25 to make it fully covered.
However, in this manner of manufacturing the skin covered foamed plastic article has a problem of leakage of the liquid foamed plastic 26 through the engagements between the outer edges 14a and 14b of the movable part 13b and the receiving edges 15a and 15b of the fixed part 13a, especially when the skin member 21 is made of sheets of foamed material such as a slub-urethane. Such a leakage often results in producing an uncomfortable seat when the skin covered foamed plastic article is used for that purpose.